Sarah Haskins is a hard core athlete. She's participating in triathlon in this year's Olympics, and between the three sports, she spends a good five hours a day training, incorporating strength training twice a week. Her strength training routine really focuses on the core, because, "In triathlon, every discipline extends from your core. If your core isn't stable, your form will fall apart, and it can even lead to injury."

To keep her core strong, Sarah incorporates ab roll-outs, side planks, walking lunges with a medicine ball, stability ball tuck-in push-ups, and a variety of balance exercises using a balance pad.

While her workout looks amazing -- I can't wait to try it out myself -- I was more interested in reading about how she overcomes challenges, like waking up when she's really sore or tired. She has specific training goals set for each session, and by concentrating on that goal, rather than the fact that she's spending five hours doing what made her so sore and tired in the first place, she's able to really get into her each session. And, of course, once she gets going, she's in the zone.